Contractors: Watch your mail.

Next month, more than 4 million U.S. businesses will receive questionnaires from the Census Bureau and Commerce Department as part of the 2007 economic census.

The checkup on the health of American businesses, done every five years, will require them to report on employment, payroll and sales. Officials from the Census Bureau say answers from about 130,000 construction-related companies will be included in the results.

Companies are required to respond to the survey and return it by Feb. 12. Information about specific firms will not be published.

“Economic census forms that businesses receive in December will tell us how we are changing as a nation,” said Thomas Mesenbourg Jr., the bureau’s associate director for economic programs. “Important economic indicators, such as gross domestic product, are directly related to the quality of the data we get from businesses in every industry and locality.”

Business owners benefit from the data as well, officials add. The information can help them determine where they stand in regards to salaries and market share on a state and national level. “I’m constantly advising entrepreneurs to consult economic census information before making decisions,” said Rhonda Adams, a syndicated columnist and small-business adviser. “It helps businesspeople make informed decisions.”

The government has established a Web site, www.business.census.gov, with more information including sample answer forms.

“We urge businesses to take advantage of the information available to them from the economic census and to watch for their census forms,” said the Census Bureau’s assistant director for economic programs, Harvey Monk.